Dynamically balanced, fluid submersible and movable object

ABSTRACT

A dynamically balanced, fluid submersible, self propelled object that may be suitable as a toy or for transporting man and material. The object, through a combination of negative and positive buoyancy, and control surfaces, can descend and ascend repeatedly. The submersible object includes a tail fin assembly of essentially four fins radially extending from the object body, and a pair of wings, where the position and size of the fins and wings are controlled and balanced by specific perimeters to ensure the self propulsion.

FIELD OF THE INVENTION

[0001] This invention is directed to the field of fluid submersible objects, more particularly to a submersible object that is dynamically balanced to be self propelled through a variety of fluids having specific gravities from below to that above water.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to a fluid submersible object which, by the combination of negative and positive buoyancy, and control surfaces, can descend and ascend repeatedly. While a preferred application for the unique design features may be as a toy or child's glider for use in water, full scale models may also made which adopt the design. Notwithstanding the above, the further description will be directed primarily to the application of the principles hereof to that of a toy submersible object.

[0003] Water toys that are used at the beach and in swimming pools come in a variety of shapes and sizes. Water balls, boogie boards, floating chairs, rubber duckies, are just a small example of the types of toys, both child and adult, that can be found at a given swimming locale. One toy that has found particular favor by both child and adult alike is a powered water vessel, either surface or subsurface. Such a vessel moves through the water and is typically propelled by a small gasoline or electric motor. The problem with this type of toy vessel is that motors are ill suited for the harsh environment of the water, especially salt water, and such toys are expensive to manufacture and to maintain.

[0004] Other toys have been proposed that eliminate the need for a motor in order to achieve vessel propulsion, typically using some energy storage device to achieve propulsion. However, these toys are either unduly complex in design and construction, and thus relatively expensive to manufacture, or have relatively unstable and thus undesirable propulsion characteristics.

[0005] The prior art teaches several recreational devices, i.e. toys, that can be used in water to simulate an underwater projectile for use by children. Three of such recreational devices are described in the following U.S. Patents:

[0006] a.) U.S. Pat. No. 5,865,662, to Dammann, teaches a weight-adjusted underwater toy having a somewhat lower specific gravity than water, and having its center of gravity located below and somewhat behind the volumetric center of the toy. The toy has a streamlined shape, like a fish, a sea animal, a swimmer, or a submarine. The model will follow a long glide curve similar to an approximately upside down ballistic path when flung into the water, and will always rotate into a position with its back up and its abdomen down. When rising, the location of the center of gravity will provide an inclined forward/upward position for the model, and horizontal side wings (fins or other details) will prevent a purely vertical rising movement by providing a forwardly directed momentum during a buoyancy movement. The weight adjustment takes place either by forming the model from a material which is heavier than water and is divided in two parts along a horizontal center section with an excavation in the top part in front of the center of the section surface, in such a manner that when joining the parts together, a sealed air pocket is formed, or by forming the model from a material which is lighter than water and has a heavier weight imbedded below and somewhat behind its volumetric center.

[0007] b.) U.S. Pat. No. 5,514,023, to Warner, relates to a recreational device in the form of an elongate projectile. The projectile has a body including a nose region, a mid-region and a tail region. Preferably, the projectile is provided with a fillable cavity for adjusting its buoyancy. The body has a size, mass, length-to-diameter ratio, specific gravity and contour that facilitate its stable distant travel through a liquid medium such as water. Importantly, the projectile has a specific gravity of between 0.95 and 1.05, which renders it neutrally buoyant in most fresh water bodies. In a preferred embodiment of the invention, the recreational device for stabilization purposes against undesirable yaw, pitch and roll has arcuately spaced, radially extending fins in a tail region of the body. When launched by hand underwater, the device maintains an imparted trajectory and slips cleanly through the water over a great distance. However, the device of Warner is limited to water, more specifically to a fluid specific gravity of 0.9 to 1.1, where fresh water is the standard of 1.0 S.P.

[0008] c.) U.S. Pat. No. 4,241,535, to Tsukuda, is directed to a submersible toy having an upper body portion and a watertight lower body portion coupled to the upper body portion. The upper body portion has a first horizontal rudder on the periphery thereof and a float disposed inside. The lower body portion has a motor and a cell disposed inside thereof, a propeller mounted on a rotary shaft of the motor, and a vertical and a second horizontal rudder disposed at the rear of the propeller. With this construction, the submersible toy can alternatingly cruise under water and on the surface.

[0009] The prior art, including existing commercial submersible objects, are all directed to toys, and are not designed for application in larger vehicles, as proposed by the present invention. The manner by which the this invention offers this broad prospective to submersible objects will become apparent in the description which follows.

SUMMARY OF THE INVENTION

[0010] The present invention is directed to a fluid submersible and movable object of a size as small as for use by a child in a swimming pool, or for the transportation of man and material in an ocean. The submersible object hereof, providing smooth and stable propulsion characteristics, comprises a dynamically balanced, elongated body tapered for and aft to a broad middle portion, four fins extending radially about a first tapered end, where said fins are angled at 90° to an adjacent said fin, and a pair of wings extending from said broad middle portion, where said wings are planarly aligned with a corresponding pair of said fins. To ensure a dynamically balanced submersible object and smooth motion thereof through a fluid, the preferred wing area to the fin area is about 6.0. Further, the total buoyancy to the total wing and fin area, for a preferred embodiment, the ratio will be in the range of about 0.025 to 0.035, with the optimum of about 0.028 lb./sq. inch. Additionally, the wing center of dynamic lift is approximately 37.5% of the length of the elongated body from the forward most tapered end, and the center of buoyancy is somewhere between the forward most end and the wing center of dynamic lift, or preferably at about 31.25%. Finally, the distance between the center of dynamic lift for the respective wing and its counterpart for the tail fin, is identical to the distance between the center of the wing area to the center of the tail fin area. However, the dynamics of the object's design recognizes that the center of gravity and the center of buoyancy are different in a static state, i.e. not submerged in fluid, but which become the same when submerged.

[0011] Accordingly, an object of this invention is to provide a dynamically balanced, submersible object that may be self propulsed within a fluid of varying specific gravities.

[0012] Another object of the invention is the provision of a design for a submersible object that can be translated from a small toy-like object to one of a size to carry man and material.

[0013] These and other objects will become more apparent in the following specification, particularly when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0014]FIG. 1 is a top plan view of the dynamically balanced, fluid submersible object according to this invention.

[0015]FIG. 2 is a side view thereof.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0016] The present invention is directed to a fluid submersible object that is self-propelled from buoyancy forces alone. The invention has broad application from small toys for children, to large man contained objects, where the object may be self-propelled through a range of fluids. The submersible object hereof will now be described with regard to the two Figures, where like reference numerals represent like components or features in the two views.

[0017] Turning now to the respective FIGS. 1 and 2, the submersible object 10 comprises an elongated body 12 having a forward tapered end 14, a rear tapered end 16, and a broadened middle portion 18 smoothly tapered to the respective ends 14, 16. Extending from the rear tapered end 16 and beyond the end are plural tail fins 20, preferably four such fins in number arranged radially thereabout at about 90 degrees. However, as will be explained later, the two side tail fins 20° are angled about 7 degrees downwardly. The submersible object 10 further includes a pair of laterally extending wings 22 disposed from opposite sides of the broadened middle portion 18. The wings 22, planarly aligned, are essentially aligned with the tail fins 20′, which as noted above are slightly angled. This modified alignment is important so that the respective wings and tail do not stall at the same speed. The differing angles of attack between the surfaces of the wings 22 and tail fins 20′ is what helps to provide dynamic balance once the object reaches its equilibrium speed. Further, it helps to dampen phugoid oscillations, where phugoid oscillations may be caused by having too high a moment of inertia. That is, typically the mass is all in the nose and tail, and as a consequence, as the nose starts to move in one direction it takes it too much time for the aerodynamic forces to reverse it, and when it finally returns to where it ought to be, it keeps on going until it is pointing too much in the other direction. This arrangement leaves the two remaining tail fins which are aligned through the object's centerline to ensure straightline flight.

[0018] In a preferred system for the submersible object according to the invention, the respective centers A1 and A2, of the surface areas of the wings 22 and tail fins 20, are about 62.5% of the length elongated body 12. Further, the respective centers D1 and D2, of the wing's and tail fin's dynamic center are forward of the corresponding said centers A1, A2, the centers D1 and D2 are also about 62.5% apart, but with the center D1 about 37.5% from the forward tapered end 14. Finally, the center of buoyancy B1 for the submersible object 10 is even more forward, about 31.25% from the forward tapered end 14. With this careful balance, and a preferred wing area to tail fine area of about 6.0, a submersible object that is self-propelled from buoyancy forces alone is achieved. However, while all these relationships are important, the most critical aspect of the invention is balance.

[0019] It is recognized that changes, variations, and modifications may be made to the submersible object of this invention without departing from the spirit and scope thereof, particularly by those skilled in the art. Accordingly, no limitation is intended to be imposed thereon except as set forth in the appended claims. 

1. A dynamically balanced, self propelled, submersible object for use in an variety of fluids of differing specific gravity, the submersible object comprising; a.) an elongated body of predetermined length having a broadened center portion tapering fore and aft to tapered ends; b.) a pair of laterally extending wings projecting from said center portion; and, c.) four radially extending tail fins at the aft tapered end, where said tail fins are about 90° apart, with an opposing pair aligned with said wings, and where said opposing tail fins are angled about 7° downwardly to ensure that said wings and said opposing tail fins do not stall at the same speed.
 2. The submersible object according to claim 1, wherein said opposing tail fins extend axially beyond said aft tapered end.
 3. The submersible object according to claim 2, wherein the surface area of a said wing is about six times that of a said tail fin.
 4. The submersible object according to claim 3, wherein the distance between the surface area centers of said wing and said tail fin is about 62.5% of said predetermined length.
 5. The submersible object according to claim 4, wherein the dynamic centers of said wings and opposing tail fins are forward of said surface area centers.
 6. The submersible object according to claim 5, wherein the center of buoyancy for said object is forward of the dynamic centers of said wings. 